(Z)-3-(2-Aminoanilino)-1-phenylbut-2-en-1-one

In the title compound, C16H16N2O, the phenyl and 2-aminophenyl rings are almost perpendicular to one another, with a dihedral angle of 82.77 (8)°. There is an intramolecular N—H⋯O hydrogen bond in the molecule. In the crystal, molecules are linked via N—H⋯O hydrogen bonds forming chains along [001]. There are also C—H⋯π interactions present, linking the chains to form a three-dimensional structure.

In the title compound, C 16 H 16 N 2 O, the phenyl and 2-aminophenyl rings are almost perpendicular to one another, with a dihedral angle of 82.77 (8) . There is an intramolecular N-HÁ Á ÁO hydrogen bond in the molecule. In the crystal, molecules are linked via N-HÁ Á ÁO hydrogen bonds forming chains along [001]. There are also C-HÁ Á Á interactions present, linking the chains to form a three-dimensional structure.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: SU2583).
In the title compound, Fig. 1, the phenyl ring (C1-C6) makes a dihedral angle of 82.77 (8)° with the 2-aminophenyl ring (C11-C16), which shows that they are almost orthogonal to each other. The amine attached with phenyl ring (C11-C16) deviates by 0.0827 (14) Å. There is an intramolecular N-H···O hydrogen bond in the molecule (Table 1 and Fig. 1) In the crystal, molecules are linked via N-H···O hydrogen bonds forming chains along the c axis direction. There are also C-H···π interactions present linking the chains to form a three-dimensional structure (see Table 1 and Fig. 2).

Experimental
To a solution of 1-benzoylacetone (2 g, 12.3 mmol) in chloroform (25 ml), 1,2-diaminobenzene (1.33 g, 12.3 mmol) in chloroform (25 ml) was added with stirring. The yellow coloured solid product was collected by filtration and washed with water to remove unreacted 1,2-diaminobenzene. The microcrystalline compound was recrystallized from hot chloroform giving yellow crystals of the title compound, suitable for X-ray diffraction analysis, on slow evaporation of the solvent [Yield: 51%; M.p. 382 K].

Special details
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2sigma(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.